VSS was:Re: BCC decodes

[D. Barry Stubbs]

Mike wrote:
> 
> perchance is this a speedo/vss with a speedo cable to the back of it? also
> is the vss on this easily removable (if the above is true?)?

As I understand it, on the 87 & 88 J cars, there is a VSS at the
transaxle itself.  Then, in 89, the VSS was moved to the instrument
cluster.  This is for digital dash version.  I'm not certain how the
analog dash versions work, seeing as how I've never messed with any
other J car except my own, which does have the digital dash.


> ----- Original Message -----
> From: "Ludis Langens" <ludis at cruzers.com>
> .....
> > Yes.  Amongst the FWD cars, the J-bodies (Cavalier) are an oddball where
> > the ECM gets the VSS signal from the instrument cluster.  The J-bodies
> > were either one of the first to get an all electronic VSS+speedo and
> > last to change to the "new" way of hooking them up, or one of the last
> > to get rid of mechanical speedo cables.

Ahhhh... this is beginning to sound familiar.  The J cars have the VSS
buffer (4000 ppm to 2000 ppm) prior to the ECM VSS input, whereas the L
& A cars have the ECM performing the VSS buffering before the VSS goes
to the instrument cluster?  I'm not sure that's right.

It may not matter to anyone except myself, so pardon me if this is
seemingly off topic.  I'm finding this VERY interesting how the VSS
signal is routed and processed by the ECM, especially since, when I do
get into chipping, several friends have L cars and this could be very
important to drivability and performance.  So thanks for the info, Senor
Langens.


========================================================================
D. Barry Stubbs                                    http://surf.to/z24man
(478) 745-9429                                     AOL IM: thez24man
z24man at earthlink.net          BNet Member #828     ICQ #5409648
#101STS MidGa Region SoloII   94 Q4 5spd Aqua Z26  88 2.8 5Spd White Z24
----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org